The present invention relates to a switching device in which a structure constituting fixed contacts is improved.
Generally, the switching device in which the fixed contact is formed by the wiring pattern on the wiring board is offered. However, the wiring board is high cost, and thus the switching devices shown in FIG. 4 to FIG. 6 are offered in place of the above switching device.
In the switching devices shown in FIG. 4 to FIG. 6, a conductor 2 is buried in an insulator 1 and a part of this conductor is exposed This exposed portion is used as a fixed contact 4 corresponding to a movable contact 3, and thus remaining portions of the conductor 2 are buried in the insulator 1 for the purpose of insulation. Therefore, bent portions M where the exposed portion is raised one step higher than other portions are formed on the conductor 2 on opposite sides (right and left sides in FIG. 4) of the exposed portion.
In the case of the illustrated example, the movable contact 3 is fixed to a bottom surface of a protruded portion 5a of a sheet 5 made of elastic member such as rubber, or the like (so-called rubber contact). The movable contact 3 when pushed by a push button 6 via a pusher 7 is brought into contact with two fixed contacts 4 (see FIG. 5) such that the contact 3 bridges over the two fixed contacts 4.
In the case of the above structure, a cost can be suppressed lower than the structure in which the fixed contact is constructed by the wiring pattern on the wiring board. However, due to a bending error of the bend portion M, a level difference S shown in FIG. 6 tends to occur between two fixed contacts 4. Therefore, there is a possibility that a contacting condition of the movable contact 3 to two fixed contacts 4 becomes uncertain since the movable contact 3 contacts one contact but may not contact the other due to this level difference S, i.e., so-called defective contact is caused.